The present invention relates to a rechargeable battery assembly for a vehicle, wherein the rechargeable battery assembly comprises a metal-air rechargeable battery.
Due to their achievable high-energy density, metal-air rechargeable batteries are suitable in particular for mobile applications, for example, for vehicles. An example of metal-air rechargeable batteries are lithium-air rechargeable batteries. Their function will be explained briefly in the following. When the lithium-air rechargeable battery is discharged, an electron is released at a lithium anode and a positive lithium ion passes through an electrolyte to the carbon cathode. At the carbon cathode, the lithium ion reacts with oxygen in a reduction process first to lithium oxide and then to lithium peroxide. In order for this reduction process to take place, the carbon cathode is coated with a catalyst, is highly porous, and comprises therefore a very large surface area. When charging the lithium-air rechargeable battery, this process is reversed. Oxygen is released at the carbon cathode; metallic lithium is deposited at the lithium anode.
The lithium anode is moisture sensitive because the metallic lithium can react violently with water. Due to its high porosity, the carbon cathode, on the one hand, is susceptible to contamination with particles such as dust or sand and, on the other hand, harmful gases contained in the air can act as catalyst poisons that can irreversibly damage the carbon cathode. Up to now, lithium-air rechargeable batteries and also other metal-air rechargeable batteries have been tested only under laboratory conditions and loaded with high-purity gases in this context.